Can an engine run or at least throw a CEL without a signal from the knock sensors?

Jamison C

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*rant ahead*

So my sister just got her car back from the mechanic. It's a Ford Fusion with a timing chain-driven internal water pump that went bad. This job requires the engine to be completely removed from the car via supporting the engine and bringing the car up around it on a lift. I do not have a lift which is the only reason this job was done by a mechanic and not myself.

I told her be careful of them trying to nickel and dime you over stupid shit. The original quote was for $1700 to replace the water pump and go ahead and do the timing chain while they were in there IF the timing chain actually needed done. She stressed that all she could barely afford the $1700 to do the work, but to go ahead and NOT do anything else. Well, she gets a call yesterday that her spark plugs and air filters need replaced and to do it while the engine is out. I tell her to tell them no, because I can do all of that stuff myself. So today, she gets a call that one of her knock sensor's wiring was "chewed through" by a rodent and needs repair. Now I do the basic maintenance on that vehicle regularly and I can assure you there are no rodents living in there. The wiring for the knock sensors also runs under the intake manifold. I wasn't there so she naively gives them the OK to do the repair.

She gets the bill back today, and the wiring repair cost $135.00!!! This wasn't wiring completely void or missing that had to be retraced, this was supposedly just a simple cut that needed a splice that would take ten minutes to repair. Now, before we sent it to the shop VIA tow truck, I checked all the codes and the only code that showed was for an EVAP leak. Nothing related to a knock sensor was stored or pending.

So my question is what the title states. They ended up nickel and diming her on several other things like the spark plugs, oil change, air filter; stuff that she did NOT authorize, which came out to an additional $400. Coincidentally, all this extra work amounted to a bill total of $1700, the amount she told them she could (barely) afford for the original job. They charged her for a diagnostic, which we already knew what the problem was, they charged her for an AC evacuation and refill, which is ridiculous because that HAS to be done with the engine removal and should be part of the labor to do the job, and they charged her for an oil change. Now if the oil needs to be changed since they're working under the timing cover, that should ALSO be included with the labor. But she had it done two weeks ao and there's no logical reason why they should have done it otherwise. And then of course, the $135 to put two wires back together. Oh and after all of this, they didn't even do the timing chain.

I think the office guy said to himself "this dumb broad can afford $1700, so we'll find $1700 worth of work to charge her for and make her think it needs done." In regards to the knock sensor, I'm convinced that while they were removing the engine, they fucked up and severed the wiring to the knock sensor and saw it as an easy way to score an additional $135. I'm gonna be having a chat with them tomorrow. Worse comes to worse, I threaten a charge back and they refund the money of work not authorized.

Thoughts?
 
5 years ago I would have taken the dealers side on this. After hearing very similar stories few female friends, I would tell the dealer to get bent and file the chargeback first.
 
What’s sad is this is supposedly a very reputable and honest local shop. Though since I moved here 11 years ago, people who have actually dealt with them have said otherwise, which is why I told my sister to be careful dealing with them. I’ll try to resolve it without threatening a chargeback. But I don’t expect to get anywhere with that.
 
I was never a Ford guy but worked as a Master tech fro Toyota & Lexus in a former career. P0325 is the standard OBDII code for the knock sensor, if it wasn't present I'd think it safe to assume the knock sensor circuit is functioning normally. A car will run with bad knock sensor or knock sensor circuit, just not as well as it should.

What do they mean by "chewed through"? Did they just see some damaged insulation and call it bad? I would definitely ask for specifics, especially how they justified $135 for a claimed wiring repair that was identified based upon a visual inspection.
 
What do they mean by "chewed through"? Did they just see some damaged insulation and call it bad? I would definitely ask for specifics, especially how they justified $135 for a claimed wiring repair that was identified based upon a visual inspection.
This is where I’m a little confused as well. I’ve dealt with pack rat damage before and they don’t chew back an entire wire to the point that you have to do some serious detective work. It’s just enough to sever the connection but it’s obvious which wires go where based on color.

They claimed it was the knock sensor, which is only two wires. I’ll find out a little more later when I go in to talk to them. I rodent would have had to chew through the wire and insulation to do that.